title: Chlorine truck attack consequences and mitigation.
abstract: We develop and apply an integrated modeling system to estimate fatalities from intentional release of 17 tons of chlorine from a tank truck in a generic urban area. A public response model specifies locations and actions of the populace. A chemical source term model predicts initial characteristics of the chlorine vapor and aerosol cloud. An atmospheric dispersion model predicts cloud spreading and movement. A building air exchange model simulates movement of chlorine from outdoors into buildings at each location. A dose-response model translates chlorine exposures into predicted fatalities. Important parameters outside defender control include wind speed, atmospheric stability class, amount of chlorine released, and dose-response model parameters. Without fast and effective defense response, with 2.5 m/sec wind and stability class F, we estimate approximately 4,000 (half within ∼10 minutes) to 30,000 fatalities (half within ∼20 minutes), depending on dose-response model. Although we assume 7% of the population was outdoors, they represent 60-90% of fatalities. Changing weather conditions result in approximately 50-90% lower total fatalities. Measures such as sheltering in place, evacuation, and use of security barriers and cryogenic storage can reduce fatalities, sometimes by 50% or more, depending on response speed and other factors.
authors.affiliation: ABS Consulting, 1525 Wilson Blvd., Ste. 625, Arlington, VA 22209, USA. abarrett@absconsulting.com
authors.forename: Anthony Michael
authors.initials: AM
authors.lastname: Barrett
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Adams
mesh_terms: D000280:Administration, Inhalation; D051337:Chemical Terrorism / Q000517:prevention & control / Q000706:statistics & numerical data; D002713:Chlorine / Q000008:administration & dosage / Q000633:toxicity*; D006801:Humans; D008962:Models, Theoretical; D018986:Motor Vehicles; D018570:Risk Assessment; D012308:Risk Management; D040242:Risk Reduction Behavior; D014505:Urban Population
chemical_list: D002713:Chlorine